1. Field of the Invention
The present invention relates to a safety latching system for a vehicle, such as may be used to fasten a spare tire thereunder. More particularly, the present invention relates to a spare tire storage and retrieval system which includes an improved safety latching system and apparatus, which is resistant to corrosion from the effects of, e.g. weathering, and salt which may be applied to roads.
2. Background Art
Many types of systems and devices have been developed for storing vehicle spare tires out of the way in, or under, vehicles in order to save space. Exemplary designs of systems for storing spare tires, on the undersides of vehicles, may be found in U.S. Pat. Nos. 3,856,167, 4,884,785, 4,915,358, 5,188,341, and 5,314,288.
In U.S. Pat. No. 4,884,785 to Denman et al., an adaptor fitting is shown and described for attaching to the end of a support cable, which may be a multifilament steel cable. The adaptor fitting of Denman has a raised central section, to which the cable is attached, and two integral flanges, which extend laterally outwardly at the bottom of the central section, on opposite sides thereof. The adaptor flange is significantly longer than it is wide.
An adaptor flange of this type is convenient to use, because it can be placed, at an angle, through a central aperture in a spare tire, with one of the flanges leading. This angled placement allows the adaptor to pass easily through the aperture. After the second flange passes through the aperture, the adaptor is then straightened out, so that the flanges fit interferingly and supportively below the metal wheel portion of the spare tire, on opposite sides of the aperture therein, to support and hold the spare tire beneath a vehicle.
A similarly dimensioned and functioning adapter flange to the flange of Denman is disclosed in U.S. Pat. No. 4,915,358 to Stallings.
The use of this type of adapter flange, as disclosed in the Denman and Stallings references, has become common. Unfortunately, this type of adaptor flange suffers from a drawback, in that, while easy to install, once in place, it leaves open gaps on either side thereof, which are open parts of the wheel aperture which are not filled thereby.
U.S. Pat. No. 5,188,341 to Greaves introduced a number of useful improvements over the previously known state of the art, at the time it was introduced. In the spare tire safety latch design of Greaves, a failsafe backup safety latch is provided to hold a spare tire in place beneath a vehicle in the event that a cable breaks. In this design, an adapter flange, which is believed to be of the general type disclosed in Denman and Stallings and discussed above, is used.
In the Greaves reference, the adaptor flange of his apparatus is referred to as a tire carrier, and has a cylindrical shank portion extending upwardly from the central section thereof, with an enlarged head at the top of the shank portion, and a flattened shoulder portion at the junction of the head and the shank portion. A pivoting member is provided, which has a pair of spaced apart latching fingers extending outwardly thereon. During normal use, when a spare tire is stowed beneath a vehicle, these latching fingers are disposed beneath the shoulder portion of the tire carrier.
Accordingly, in the apparatus of Greaves, if the support cable attached to the fire carrier should break, or otherwise fail, the latching fingers will still continue to support the tire beneath the vehicle, until such time as they are moved out of engagement with the tire carrier.
The only way that the latching fingers can be moved out of engagement with the tire carrier, according to the teaching of Greaves, is by inserting a handle end into a hollow cylinder, in a normal sequence of actions taken by a motorist in a process of dismounting the spare tire. When the handle end is inserted into the hollow cylinder, it displaces a pivotally mounted lever, which is linked by a rod to the pivoting member of the latch mechanism. Pivotal movement of the lever actuates the rod which moves the pivoting member to back the latching fingers out of engagement with the tire carrier.
While the mechanism disclosed by the Greaves reference has many useful features, including a beneficial safety latch for supporting a spare tire even when a cable fails, it nonetheless includes many metal and other moving parts which are openly exposed to the ambient environment underneath a vehicle.
In certain climates, such as, for example, in the Northeastern U.S. and Canada, road crews commonly spread salt on the roads in the winter to help combat ice and snow thereon. When a particular vehicle, which is equipped with a spare tire that is mounted therebelow, using an adaptor flange of the above-described type, is driven in an environment in which salt is on the road surface, it is entirely possible and foreseeable that corrosive salty water, from the salt-treated roads, may splash up into the spare tire support apparatus, through the aforementioned gaps in the spare tire aperture.
It is well established that salt water has a corrosive effect on metals, and especially on ferrous metals, causing oxidation, rusting, and deterioration thereof. It is therefore evident that an unprotected mechanism supporting a spare tire, beneath a vehicle, may suffer corrosion and deterioration from the effects of such salt water, and may fail if exposed to this type of environment over a period of years. Normal rain water may be corrosive to ferrous metal parts exposed underneath the exterior of a vehicle, and salt water exacerbates and accelerates such normal corrosion.
In a worst case scenario, a latch mechanism such as that taught by the prior art, after a number of years of operation, may become frozen and stuck in place by the effect of rust, and when a user wishes to change a flat tire, the spare may not be removable if parts are inoperable such as, for example, the latching fingers cannot be displaced from engagement with a tire carrier.
Accordingly, a need exists in the art for an improved safety latch for storing a spare tire beneath a vehicle, which includes sealing means for resisting water entry thereinto. More broadly, a need exists in the art for a spare tire storage and retrieval system for use with a spare tire stored beneath a vehicle, in which selected components of the system, which could possibly be compromised over time if exposed to salt water, are sealed from entry of such salt water thereinto.